Typewriting machine



Jan. 21, 1936. c, GABRIELSON TYPEWRITING MACHINE 5 0 s w mm 2 M r. Wm M92W 1! w w d 23 .M 4 x J ATTORN EYS Patented Jan. 21, 1936 I UNITEDSTATES PATENT OFFICE TYPEWRI'IING MACIHNE.

Carl G'abriel'son, Syracuse, N. Y1, assignor to L O; Smith & CoronaTypewriters, Inc., Syracuse, N. Y., a corporation of New YorkApplication October 5, 1934, Serial No. 746,949

Claims. (01. 197-74) machine parts and to the operatorsfinger when the.shift key is violently actuated.

To the foregoing ends, andother ends which 1'5 will appear from. thefollowing description of the preferred embodiment of theinvention shownin the: accompanying drawing, the invention consists of the combinationsof? elements, arrangements of" parts, and. features of construction. 20:pointed out in the appended claims and hereinafter described. In thedrawing:

Fig. 1 is a fragmentaryfront view, with certain parts broken away,showing so much. of the ma- 2'6 chine as is necessary for anunderstanding of the present invention; and

Fig; 2 is a fragmentary vertical longitudinal sectional view takenmedially of the machine.

The type bar supporting segment It carries in 30' a known manner the.pivoted type bars, one of which is shown at l I in Fig. 2; andsaidsegment is supported in a known manner in the main frame [2 of themachine. is supported in an upwardly and rearwardly in- 353 clined planeto shift down and up in said plane,

the supporting means for the segment comprising raceways I3 at the endsof the segment, race-- ways [4 on the main frame opposedto raceways l3,a pair of ball bearings l 5, one in each pair of opposed raceways l3l4,a pair of rigidarms l6 spaced apart transversely of the. machine andextending downward and forward from the lower edge of the medial portionof the segment, a horizontal rock shaft ll extending transverselyof themachine and journalled on a pair of bear ing screws I8 carriediby themain frame, a pair. of rock arms. l9 extending forward fromthe rockshaft and connected attheir forward ends to. the lower ends of arms I6ofthe segment by horizontal pivots 20, aforwardly extending rock arm 2|onthe rock shaft at one end of the shaft and having a lateral anddownward extension 21 and a return pull spring 2'2 for the segment,which spring is'anchored atits rear end to the lower end-ofextensionZWandisanchored at its for- As shown, the segment ward endtothe main frame at 23 to normally shift the segment upward and hold itup in. its normal lower case printing position.

The machine has the usual roller platen 24 supported on the usualcarriage (not shown) mounted on the main frame. The type barsareactuated in the usualmanner' by key levers (not shown) to strike to acommon printing. point on the platen, each type bar carrying as usual alower case type 25 and an upper case type 26. -0:

The improvements will now be described.

A stud bolt 21, threaded? intotthe. lower edge of the segment midwaythe. ends of the segment, extends downward and forward from the segmentin the plane of case shift movement. of the 5.

segment. This stud bolt? is provided with: an upper case stop in theform ofa collar 28 on the. bolt having over its lower face asound-deadening and vibration absorbing cushion. in. the form of arubber washer 29:- on. the bolt; Said stud bolt is also provided with alower case stop-J in. the form of-a nut 30 which is screwed on the boltand has over its upper face a sound-deadening and vibration absorbing.cushion in the formofa rubber washer 3| on the bolt.

The stops 28 -49 and 30.3l coact with. aframe stop consisting of aslightly resilient sheet! metal bar or strap 32. Bar 32 is relativelylong and extends flatwise transversely of the machine below the segmenta substantial distance'to both the right and left of the stud bolt 21;The. bar 32 is bolted to the main frame at each end of the bar by meansof two bolts 33 provided with. clamping nuts 34. The bar 32 is supportedout of contact With the main frame by vibrationabsorbing and 35sound-deadening rubber washers 35: which are mounted on bolts 33 and areclamped" between the main frame and the underface of the bar 32. Midwayits ends the bar ispermanently bent upward to provide a relativelystiflmedial yoke-like bar portion 32 'the cross-element of which istilted to lie in a plane perpendicular to the stud bolt 21 and isprovided with an aperture through which said bolt loosely extends.

The stop 30-3l normally abuts the lower face of said cross-element ofsaid yoke-like medial shifting the segment downward into its lower caseprinting position, and said improved means will now be described.

A shift key lever, 36 carrying a shift key 31 at its forward end isfulcrumed at its rear end at 3'8 on the main frame and is normally heldrocked upward against a suitable stop 39 on the main frame by a keylever return spring 40 which is anchored to the key lever and to themain frame. A pendent pull link 4!, which is pivoted at its upper end bypivot 42 to the forward end of the arm 2i of the rock shaft IT, has ayieldable connection at its lower end with the shift key lever 36between the fulcrum of said lever and the shift key 31.

This yielding connection comprises a three-arm lever located at one sideof key lever 36 and piv0ted thereon by a horizontal pivot 43 whichextends transversely of the machine. The three arms of said three-armlever extend from its pivot, one arm 44 extending rearwardly, an arm 45extending forwardly, and an arm 46 extending up wardly, from the pivot43. Arm 44 has thereon a laterally extending pin 41 pivotally engagedwith the lower end of link'4l, preferably by being engaged in the lowerend of a vertical slot 48 in said link. Arm 45 is a stop arm coactivewith an overhanging stop 49 fixedly held or riveted at 50 to the keylever 36, said stop arm preferably having an adjustable up-and-downextending stop screw 5! threaded therethrough to, engage with its upperend under the overhanging stop 49. A look nut 52 is preferably threadedon the stop screw to engage the under face of the lever arm 45. Toyieldingly hold the stop armengaged by means of the upper end of screw5i under the stop 49, said stop 49 is provided with an upstanding lug 53through a suitable aperture in which is loosely slidable the forwardportion of a foreand-aft extending plunger 54 which is pivoted at itsrear end to the upper end of arm 46 of the three-arm lever by ahorizontal pivot 56 which extends transversely of the machine, aboutwhich plunger is coiled a compression spring 55 which abuts at itsforward end the rear face of lug 53 and abuts at its rear end shouldersformed by;

enlargement of the rear end portion of the plunger.

Upward movement of the segment by return spring 22 is arrested byengagement of stop 3ll--3l under frame stop 3232 as shown in Figs. 1 and2. The strength of spring 22 is such that said spring is not strongenough to hold the slightly resilient bar il232 bowed or flexed, and thesegment will, therefore, instantly come to rest in its proper lower caseprinting position upon impact of stop 30-3l with said bar. Cushion 3| ofstop 3U3l and the slightly resilient frame stop 32-42 silently andaccurately bring the segment to rest in its normal elevated lower caseprinting position. The sheet metal stop 32-32 has a different period ofvibration from that of the cast metal main frame andthe cast metalsegment and is, furthermore, supported on the rubber pads 35, so thatvibrations due to shock incident to arrest of the upward movement of thesegment produce substantially no audible sound.

To shiftthe segment downward to its upper case printing position theshift key 31 is depressed to rock the rock shaft ll through the arm 2 l,link 4|, and the yielding connection between said link and the key lever36. The segment, upon depression of the shift key to the position shownin dotted lines in Fig. 2 ,'is silently'arrested in its upper caseprinting position by engagement of stop 2829 with stop bar 32-32 Ifexcessive down thrust is coninued on the shift key after stop 28-29engages bar 32-32 spring 55 will be compressed and the key lever maycontinue its downward movement until arrested by engagement of said keylever with a stop 5'! on the main frame. Spring 55 is not strong enoughto permit the stop bar to be held bowed or flexed by pressure whichcanbe exerted on the shift key to compress spring 55. The segment,therefore, will instantly come to rest in its proper upper case printingposition upon impact of stop 2829 with bar 32--32 even when the keylever is carried down against stop 5? by a violent blow on the shift keyor by an .excessive pressure maintained on the key after stop 28-49abuts bar 32-322". Bar

3232 while sufficiently resilient to vibrate minutely under impact ofstops 2829 and 3'll3 l, is sufficiently stiff relatively to springs 22and 55 to practically instantaneously resume a neutral nonflexedposition after impact of either of said stops thereagainst. By theimprovements described, provision is made for shifting the segment topredetermined case positions at which it is arrested both silently andaccurately.

What I claim is: l

1. A typewriting machine having a main frame, a support mounted in themain frame for shifting movement from one to the other of two positionsto condition the machine for printing upper and lower case characters,two spaced stops movable with said support, and a resilient metal strapheld at its opposite ends to the main frame with the strap free fromcontact with the main frame intermediate its held ends for engagement ofsaid stops with the opposite faces of said strap substantially midwaybetween the ends of the strap to arrest the support in said twopositions.

2. A typewriting machine, as claimed in claim 1, wherein each of saidstops has a strap-engaging face of vibration-absorbing andsound-deadening material, such as rubber.

3. A typewriting machine as claimed in claim 1, wherein pads ofsound-deadening and vibrationabsorbing material, such as rubber, areinterposed between the held ends of the strap and the main frame, andeach of the two spaced stops has its strap-engaging face covered with apad of sound-deadening and vibration-absorbing material, such as rubber.

4. A typewriting machine having a main frame, a support shiftable in themain frame to condition the machine for upper and lower case printing, apair of spaced stops shiftable with the support, a slightly resilientsheet metal stop held to the main frame and interposed between said pairof spaced stops for engagement of said spaced stops alternately withsaid sheet metal stop, a return spring connecting said support and frameto shift the support to and normally hold it in a lower case printingposition in which said sheet metal stop is abutted by one of said spacedstops, a shift key lever fulcrumed on the main frame, and means forminga yieldable connection between said key lever and support for shiftingsaid support into an upper case printing position in which said sheetmetal stop is abutted by the other one of said spaced stops, saidresilient sheet metal stop being sufficiently stiff to assume anon-flexed position while either of the said spaced for engagement ofthe spaced stops with opposite faces of said strap substantially midwaythe ends of the strap.

6. A typewriting machine, as claimed in claim 4, wherein the sheet metalstop is a strap of sheet metal which is spaced from the main framebetween the ends of the strap and is held only at its ends tothe mainframe, sound-deadening pads are interposed between the held ends of thestrap and the main frame, and said strap is held to the main frame forengagement of said spaced stops with the opposite faces of the strapsubstantially midway the ends of the strap.

7. A typewriting machine having a main frame, a type bar supportingsegment mounted in the main frame to shift in an up-and-down directionfor case-changing purposes, key-controlled means for shifting thesegment between upper and lower case printing positions, a rigid stopcarrier depending from said segment substantially midway the ends of thesegment, upper and lower case stops carried by said carrier and spacedapart longitudinally of the carrier, and a resilient metal strapextending transversely of said carrier and having an aperture thereinsubstantially midway its ends through which said carrier is slidablewhen the segment is shifted, said strap being secured at its ends to themain frame with the strap out of contact with the frame intermediate thesecured ends of the strap for abutment of one of said stops with theupper face of the strap to arrest the segment in one of said caseprinting posi- 5 tions and for abutment of the other one of said stopswith the lower face of the strap to arrest the segment in the other oneof the case printing positions of the segment.

8. A typewriting machine as claimed in claim 7, characterized in thatsaid key-controlled means for shifting the segment comprises a key leverfulcrumed on the main frame, a frame shaft journalled on the main frameand connected to the segment to shift the segment, and means forming ayieldably extensible operating connection between said key lever androck shaft for rocking the shaft.

i 9. A typewriting machine as claimed in claim 7, characterized in thatsound-deadening pads are interposed between the main frame and the twoends of said strap.

10. A typewriting machine as claimed in claim '7, characterized in thatthe segment is shifted in both directions by yieldable means.

CARL GABRIELSON.

